Cervical cancer is one of the most common cancers in women worldwide. Since invasive disease is preceded by pre-malignant Cervical Intraepithelial Neoplasia (CIN), if detected early and treated adequately, cervical cancer can be universally prevented. For this reason, early detection of cancerous and precancerous lesions is particularly important at preventing the progression of the disease.
Colposcopy involves visually inspecting the cervix of patients who have some prior indication of abnormality. The procedure is conventionally performed by using a colposcope. The colposcope typically comprises a light source to illuminate a region of interest within a subject, e.g., the cervix of a patient, and an image sensor (e.g. a Charge-Coupled Device detector, i.e. CCD detector) to acquire an image of the region of interest. The acquired image will be provided to a clinician. Such colposcopic examination can be used by the clinician to identify and rank the severity of lesions, and thus a biopsy sampling of cervical tissue representing the highest-grade abnormality, may be taken, if necessary.
In order to reliably assess colposcopic features, the imagery must be of high visual quality. One factor leading to poor cervical imagery is specular reflection (i.e. glint). Usually, glint is undesirable because it effectively eliminates color information in an image (the color information can represent tissue structure and can be important in detecting cancer precursors). Reducing the amount of glint in an image is helpful in producing high-quality images for diagnostic purposes.